眼角膜曲率仪的测量和设计原理

The Measurement on and the Designing Principle of the Opathalmometer

眼角膜曲率仪又称角膜计,是应用光学方法测量人眼眼球的一种光学仪器。测量是通过光学系统中心两个光标,从角膜反射经透镜组和两组光楔测微补偿器的轴向调节来测出两个光标象的间隔,再计算出曲率半径和有关光学量的数学函数式,因此本文眷重叙述和推导了函数关系。本文最后分析了影响被测半径精度的各种因素。

Ophthalmometer is an Optical instrument that is capable of measuring the corneal radius of man's eyeballs by means of optics. Measurement is carried out through two differential light targets in the optical system, from cornea reflection via the lens set by virture of the axial adjustment of two sets of prismminimeter compensators, thus measuring out the intervals of two prism images and then calculating the radius of curvature. Considering that the formulae of mathematical function of measured radius and the optical quantity concerned are not available in the existing documents, this article has emphatically desctibed and derived the functional relation. In the last part of this artical the various factors which influence the precision of the measured radius have also been analyzed.